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object Test extends App {
val s0: Stream[Int] = Stream.empty
println(s0.take(1))
println(s0.takeWhile(_ > 0))
println(s0.lengthCompare(-5) > 0)
println(s0.lengthCompare(0) == 0)
println(s0.lengthCompare(5) < 0)
println
val s1 = Stream.cons(1, Stream.empty)
println(s1.toArray.deep)
println(s1.take(1))
println(s1.take(2))
println(s1.drop(1))
println(s1.drop(2))
println(s1.drop(-1))
println(s1.dropWhile(_ > 0))
println(s1.lengthCompare(-5) > 0)
println(s1.lengthCompare(0) > 0)
println(s1.lengthCompare(1) == 0)
println(s1.lengthCompare(5) < 0)
println
val s2 = s1.append(Stream.cons(2, Stream.empty))
println(s2.toArray.deep)
println(s2.drop(1))
println(s2.drop(2))
println(s2.drop(-1))
println(s2.dropWhile(_ > 0))
println(s2.lengthCompare(-5) > 0)
println(s2.lengthCompare(0) > 0)
println(s2.lengthCompare(1) > 0)
println(s2.lengthCompare(2) == 0)
println(s2.lengthCompare(5) < 0)
println
val s3 = Stream.range(1, 1000) //100000 (ticket #153: Stackoverflow)
println(s3.length)
// ticket #153
def powers(x: Int) = if ((x&(x-1)) == 0) Some(x) else None
println(s3.flatMap(powers).reverse.head)
// large enough to generate StackOverflows (on most systems)
// unless the following methods are tail call optimized.
val size = 100000
// test tail recursive methods
println(Stream.from(1).take(size).last)
println(Stream.from(1).drop(size))
println(Stream.from(1).filter(_ > size).take(5))
println(Stream.from(1).take(size).forall(_ >= 0))
println(Stream.from(1).exists(_ > size))
Stream.from(1).take(size).foreach( x => () )
println(Stream.from(1).take(size).foldLeft(0)(_ + _))
val arr = new Array[Int](size)
Stream.from(1).take(size).copyToArray(arr, 0)
println
// ticket #6415
lazy val x = { println("evaluated"); 1 }
val s4 = 0 #:: x #:: Stream.empty
println(s4.isDefinedAt(0))
}
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